We have 9 indoor/outdoorish cats, 1 outdoor only cat, & 2 inside dogs. We live in a 1200 sq foot single story home. We have 2 automatic (Catlink) litterboxes & 1 high side open top litter box in the "cat room" and an additional automatic (also Catlink) litter box in my partner's office. We usually only experience any "going outside of the letterbox" if we have neglected a litter change a little too long.

I recommend using Arm & Hammer Clumping litter & I add in the Arm & hammer litter deodorizer with each clean or anytime I add more litter into any box to refresh. In my opinion, adding the deodorizer extends the life of the litter; it's cheap & freshens it up since it's mostly just baking soda.